Games like Memo to the Underlord
Games like Memo to the Underlord include Hades, UnderMine, Shape of Dreams, Megabonk, and The Binding of Isaac. We matched them by the tags players give Memo to the Underlord on Steam (Action Roguelike, Dungeon Crawler, Action, Roguelite, and Arcade): closest matches first, and among equally close ones the better-known games.

Hades
Shared: Action Roguelike · Roguelite · Action

UnderMine
Shared: Action Roguelike · Dungeon Crawler · Roguelite

Shape of Dreams
Shared: Action Roguelike · Roguelite · Action

Megabonk
Shared: Action Roguelike · Roguelite · Action

The Binding of Isaac
Shared: Action Roguelike · Action · Procedural Generation

Vampire Survivors
Shared: Action Roguelike · Roguelite · Action

BALL x PIT
Shared: Action · Roguelite · Action Roguelike

Hades II
Shared: Action · Roguelite · Action Roguelike

Deep Rock Galactic: Survivor
Shared: Action Roguelike · Roguelite · Top-Down

Cinderia
Shared: Action Roguelike · Roguelite · Action

The Binding of Isaac: Rebirth
Shared: Action Roguelike · Dungeon Crawler · Indie

Heroes of Hammerwatch II
Shared: Action Roguelike · Dungeon Crawler · Action

Cult of the Lamb
Shared: Action Roguelike · Dungeon Crawler · Roguelite

Halls of Torment
Shared: Action Roguelike · Roguelite · Action

Skul: The Hero Slayer
Shared: Action Roguelike · Action · Roguelite

Heroes of Hammerwatch
Shared: Action Roguelike · Roguelite · Dungeon Crawler

Yet Another Zombie Survivors
Shared: Action Roguelike · Roguelite · Arcade

Sephiria
Shared: Action Roguelike · Roguelite · Action

Dungreed
Shared: Action Roguelike · Roguelite · Action

Tiny Rogues
Shared: Action Roguelike · Dungeon Crawler · Roguelite

Mortal Sin
Shared: Action Roguelike · Dungeon Crawler · Action

Enter the Gungeon
Shared: Action Roguelike · Dungeon Crawler · Action

Moonlighter
Shared: Dungeon Crawler · Roguelite · Action Roguelike

Soulstone Survivors
Shared: Action Roguelike · Roguelite · Action